JPH08121887A - Refrigerating machine using non-azeotrope refrigerant - Google Patents

Abstract

PURPOSE: To increase the controlling width of capacity control by expediting the storages of a low boiling point refrigerant and a high boiling point refrigerant in a tank even if the capacity of the tank and the refrigerant charge amount in a system are not increased more than required, improving the followability of the capacity control, and increasing the refrigerant quantity capable of holding in the tank in the case of capacity control by altering the circulation composition of the high and low boiling point refrigerants. CONSTITUTION: A tank 6 is cooked by a refrigerant of the lowest temperature before passing an evaporator of the output side refrigerant of a pressure reducing mechanism 3, liquefication of a low boiling point component is expedited, the tank 6 is cooled by the refrigerant of the lowest temperature to reduce the internal pressure, and the more low boiling point component is held in the tank 6.

Description

Detailed Description of the Invention

[0001]

This invention relates to a high boiling point refrigerant R22.
, A mixed refrigerant using R13B1 as a low boiling point refrigerant, HFC134a as a high boiling point refrigerant, a mixed refrigerant using HFC32 as a low boiling point refrigerant, or HFC134 as a high boiling point refrigerant.
a relates to a refrigerating apparatus that uses non-azeotropic mixed refrigerants such as a mixed refrigerant that uses HFC32 / 125 as a low boiling point refrigerant.

[0002]

2. Description of the Related Art Conventionally, a refrigerating apparatus using this kind of non-azeotropic mixed refrigerant can control its capacity by changing the composition ratio of a high boiling point refrigerant and a low boiling point refrigerant which are circulated in the refrigeration cycle system. Therefore, compared to the capacity control by the compressor unloader mechanism or the like, there is an advantage that the performance efficiency (COP) is less likely to decrease due to the decrease in load factor.

An example of such a refrigerating device is Japanese Patent Laid-Open No. 60-
There is one disclosed in Japanese Patent No. 142162. This is, as shown in FIG. 10, a compressor P, a condenser C, a first
A mixed refrigerant of a high-boiling-point refrigerant and a low-boiling-point refrigerant is enclosed in a refrigeration cycle system in which the second depressurizing mechanisms V1 and V2 and the evaporator E are sequentially connected, and the first and second depressurizing mechanisms V1 and V2 are included. A gas-liquid separator A for separating a condensate containing a large amount of high-boiling-point refrigerant and a non-condensable gas containing a large amount of low-boiling-point refrigerant is interposed in the intermediate pressure region between the two, and at the outlet of the evaporator E, Evaporator E
The tank part B for exchanging heat with the refrigerant on the outlet side is provided, and the upper gas region of the gas-liquid separator A and the tank part B are connected to the first opening / closing mechanism G.
1, and the tank B and the suction pipe L are connected via a second communication passage J2 having a second opening / closing mechanism G2.

Thus, by opening the first opening / closing mechanism G1 and closing the second opening / closing mechanism G2, the refrigerant containing a large amount of low boiling point refrigerant is liquefied and stored in the tank B, and the refrigerant containing a large amount of high boiling point refrigerant is circulated. I am trying to do low capacity driving. In addition, the first opening / closing mechanism G1 is closed and the second
By opening the opening / closing mechanism G2, the low boiling point refrigerant in the tank portion B is released into the system, and the refrigerant in a state in which the low boiling point refrigerant and the high boiling point refrigerant are mixed at a predetermined composition ratio is circulated to increase the temperature. I am trying to drive.

[0005]

However, in the non-azeotropic mixed refrigerant, the isotherms are not parallel to the horizontal axis as shown in the Mollier diagram of FIG. 11, and the inlet b of the evaporator E has the lowest temperature. The temperature of the refrigerant at the outlet b'of the evaporator E increases from the minimum temperature because the temperature increases as the degree of dryness increases as the evaporation progresses, and the low boiling point in the tank B is reached. Liquefaction of the refrigerant is slow and a time delay occurs in capacity control.
There is a problem that the holding pressure in the tank part B becomes relatively high and the amount of refrigerant that can be recovered from the gas-liquid separator A to the tank part B becomes small. Further, in order to avoid these, there is a problem that it is necessary to increase the capacity of the tank B or increase the amount of refrigerant charged in the refrigeration cycle.

The main object of the present invention is to promote the liquefaction of the low boiling point refrigerant in the tank without increasing the tank capacity and the refrigerant filling amount more than necessary, and to improve the followability of capacity control. The point is to provide a refrigerating apparatus using a non-azeotropic mixed refrigerant that can increase the amount of refrigerant that can be held in a tank and can expand the control range of capacity control.

[0007]

In order to achieve the above-mentioned main object, the invention according to claim 1 provides a refrigerating cycle system in which compression, condensation, decompression and evaporation are repeated as shown in FIG. In a refrigerating apparatus using a non-azeotropic mixed refrigerant in which a mixed refrigerant of a high-boiling-point refrigerant and a low-boiling-point refrigerant is enclosed, a separation liquid that separates a condensate containing a large amount of a high-boiling-point refrigerant and a non-condensing gas containing a large amount of a low-boiling-point refrigerant Part 5 and tank part 6 for exchanging heat with the low temperature refrigerant after decompressing the condensate containing a large amount of high boiling point refrigerant
And the upper gas region of the separation unit 5 and the tank unit 6 are connected via a first communication passage 81 having a first opening / closing mechanism 71, and the tank unit 6 and the low-pressure unit in the refrigeration cycle are connected to each other. The connection was made via a second communication passage 82 having two opening / closing mechanisms 72.

According to a second aspect of the present invention, in the first aspect of the invention, not only the low boiling point refrigerant can be held but also the high boiling point refrigerant can be held, and the control range of the capacity control can be increased by changing a wide composition ratio. For further expansion, as shown in FIG. 3, the non-evaporated liquid containing a large amount of the high-boiling-point refrigerant and the evaporative gas containing a large amount of the low-boiling-point refrigerant are separated from each other to have a predetermined capacity for storing the non-evaporated liquid containing a large amount of the high-boiling point refrigerant. The low-pressure tank 90 is provided, and the lower portion of the low-pressure tank 90 and the suction portion of the compressor are connected to the third opening / closing mechanism 7
They are connected via a third communication passage 83 having a number 3.

According to a third aspect of the present invention, in the first aspect of the invention, one tank portion 6 is also used so that, in addition to the low boiling point refrigerant, a high boiling point refrigerant can be held in place of the low boiling point refrigerant. In order to make it possible to change a wide range of composition ratios and further expand the control range of capacity control, as shown in FIG. 5 or FIG. 6 to FIG. A low-pressure separator 9 for separating gas from the low-pressure separator 9 is provided, and the lower portion of the low-pressure separator 9 and the tank 6 are allowed to flow only from the low-pressure separator 9 to the tank 6. And a low pressure part in the refrigerating cycle are connected to each other through a third communication passage 83 having a fourth opening / closing mechanism 74.
Connection was made via a communication passage 84.

The invention according to claim 4 is the same as the invention according to claim 1 or claim 2 or claim 3, wherein the high boiling point refrigerant and the low boiling point refrigerant are well separated.
Alternatively, as shown in FIG. 5 or FIG. 7, a separation unit 5 for separating a condensate containing a large amount of high-boiling-point refrigerant and a non-condensable gas containing a large amount of low-boiling-point refrigerant is installed downstream of the heat exchanger serving as a condenser. It is a gas-liquid separator 51 that does.

According to a fifth aspect of the present invention, in the first, second or third aspect of the present invention, a high boiling point refrigerant and a low boiling point refrigerant are efficiently separated by using a condenser. As shown in FIG. 3, the heat exchanger that is a condenser is an external condensation type having a shell Sa that releases the refrigerant and a cooling water pipe Ta that is installed therein, and is a condenser that contains a large amount of high-boiling-point refrigerant. The separation unit 5 for separating the liquid and the non-condensable gas containing a large amount of the low boiling point refrigerant is the shell Sa of the external condenser.

The invention according to claim 6 is the same as claim 5 in the invention according to claim 1 or claim 2 or claim 3, in which a high boiling point refrigerant and a low boiling point refrigerant are efficiently used by utilizing a condenser. For separation, as shown in FIG. 8, a heat exchanger serving as a condenser includes a shell Sb for generating hot water, a refrigerant pipe Tb provided in the shell Sb, and a refrigerant inlet / outlet header H.
1, H2 is an in-tube condensing type, and a separation unit 5 for separating a condensate containing a large amount of high-boiling-point refrigerant and a non-condensable gas containing a large amount of low-boiling-point refrigerant is a header H2 on the condensing refrigerant outlet side. It has a certain structure.

According to the invention of claim 7, in which the high boiling point refrigerant can be held, in order to efficiently separate the high boiling point refrigerant and the low boiling point refrigerant by using the evaporator, Similarly, as shown in FIG. 8, a heat exchanger serving as an evaporator is of a pipe evaporation type having a shell Sb for generating cold water, a refrigerant pipe Tb installed therein, and headers H1 and H2 for taking in and out the refrigerant. In addition, the low-pressure separation section 9 for separating the non-evaporated liquid containing a large amount of high-boiling-point refrigerant and the evaporative gas containing a large amount of low-boiling-point refrigerant is the header H1 on the evaporative refrigerant extraction side.

The invention according to claim 8 is the invention according to any one of claims 1 to 7, which is a relatively large-scale separate air heat source heat pump system for building air-conditioning, etc. In order to allow the tank portion 6 to be sufficiently cooled even when there is a pressure increase corresponding to the liquid head at the outlet portion of the tank portion 6, as shown in FIG.
Is a pressure reducing means 30 provided separately from the pressure reducing mechanism 3 of the main refrigerant circuit.
The heat exchanger exchanges heat with the low-temperature refrigerant whose pressure is reduced by.

[0015]

In the invention described in claim 1, as shown in FIG.
When performing low capacity operation, the first opening / closing mechanism 71 is opened and the second opening / closing mechanism 72 is closed. Thereby, the separating unit 5
Then, the non-condensed gas c containing a large amount of the low boiling point refrigerant separated from the condensate a ′ containing a large amount of the high boiling point refrigerant flows into the tank portion 6 through the first communication passage 81, and in the tank portion 6, the high boiling point The condensed liquid containing a large amount of refrigerant is cooled by the low temperature refrigerant b after being decompressed, and is liquefied and stored inside the tank unit 6. In this way, the refrigerant containing a large amount of the high boiling point refrigerant circulates in the refrigeration cycle, and low capacity operation can be performed.

On the other hand, when performing high-capacity operation, the first opening / closing mechanism 71 is closed and the second opening / closing mechanism 72 is opened, so that the low boiling point component stored in the tank portion 6 is the second communication passage 8
After being discharged into the system of the refrigeration cycle via 2, the refrigerant in a state where the low boiling point refrigerant and the high boiling point refrigerant are mixed at a predetermined composition ratio circulates, and high capacity operation can be performed.

During low capacity operation in which the tank portion 6 holds a low boiling point component, as shown in FIG. 2, the low temperature refrigerant b after depressurizing the condensate containing a large amount of the high boiling point refrigerant in the tank portion 6, that is, Since the refrigerant b containing the low boiling point refrigerant is cooled by the lowest temperature refrigerant b before passing through the evaporator, the liquefaction of the low boiling point component in the tank portion 6 can be promoted.

Moreover, since the refrigerant is cooled with the lowest temperature in this way, the condensate saturation pressure e of the low boiling point component in the tank portion 6 can be lowered, and the low boiling point refrigerant that can be held in the tank portion 6 can be increased. That is, as the recovery of the low-boiling-point refrigerant from the separation section 5 to the tank section 6 progresses, the composition of the circulating refrigerant in the refrigeration cycle shifts to the high-boiling-point component side, and the condensing temperature is considered to be constant. The condensation pressure of is decreasing (Fig. 2
At, a ′ drops in pressure to a ″). When cooling with the conventional evaporator outlet refrigerant b ', the saturation pressure d in the tank part
Is relatively high and the pressure a ″ in the separation section becomes equal to this saturation pressure d, the outflow from the separation section to the tank section stops, but in this invention, the saturation pressure e in the tank section 6 is low. As a result, a larger amount of the low boiling point component can be flown into the tank portion 6, and the amount of the low boiling point component that can be held in the tank portion 6 can be increased.

In this way, the liquefaction of the low boiling point refrigerant in the tank portion 6 can be promoted without increasing the capacity of the tank portion 6 or the amount of refrigerant filled in the refrigeration cycle system more than necessary, and the ability control followability can be improved. It is possible to increase the amount of refrigerant that can be retained in the tank portion 6 and to expand the control range of capacity control.

According to the second aspect of the invention, as shown in FIGS. 3 and 4, the low pressure tank 90 contains a large amount of high boiling point refrigerant by controlling the humidity of the refrigerant b'on the outlet side of the evaporator. The non-evaporated liquid f can be separated and stored from the evaporated gas containing a large amount of the low boiling point refrigerant. Third opening / closing mechanism 73
The high-boiling point component can be retained in the low-pressure tank 90 when closed, and the high-boiling point component in the low-pressure tank 90 can be released into the system of the refrigeration cycle when the third opening / closing mechanism 73 is opened. Thus, in addition to holding and releasing the low-boiling point component in the tank portion 6, the holding and releasing of the high-boiling point component in the low-pressure tank 90 can also be performed, and a wide range of composition ratios can be changed, further increasing the control range of capacity control. Can be expanded.

According to the third aspect of the invention, as shown in FIG. 5, the first opening / closing mechanism 71 is opened and the second to fourth opening / closing mechanisms 7 are opened.
By closing 2, 73, 74, the low boiling point component can be retained in the tank portion 6, the second opening / closing mechanism 72 is opened, and the first, third, and fourth opening / closing mechanisms 71, 73, 74 are closed. As a result, the low boiling point component held in the tank portion 6 can be released into the system of the refrigeration cycle. Further, by controlling the humidity of the refrigerant on the outlet side of the evaporator, the low-pressure separation section 9 can separate the non-evaporated liquid containing a large amount of high-boiling-point refrigerant and the evaporated gas containing a large amount of low-boiling-point refrigerant. The mechanism 74 is opened to equalize the tank portion 6 to a low pressure and the third
The opening / closing mechanism 73 is opened, and the first and second opening / closing mechanisms 71, 7 are further opened.
By closing 2, the high boiling point component separated in the low pressure separation section 9 can be retained in the tank section 6, and by opening the second opening / closing mechanism 72, the high boiling point component retained in the tank section 6 can be retained. It can be released into the system of the refrigeration cycle. In this way, the low boiling point refrigerant and the high boiling point refrigerant can be selectively retained in one tank part 6, and a wide composition ratio can be changed while keeping the number of containers having a large capacity to a minimum. Can be further expanded.

According to the fourth aspect of the present invention, as shown in FIG. 1 or FIG. 3 or FIG. 5 or FIG. 7, the high boiling point refrigerant is provided by the gas-liquid separator 51 provided downstream of the heat exchanger as the condenser. And the low boiling point refrigerant can be separated well.

According to the fifth aspect of the present invention, as shown in FIG. 6, the condensate containing a large amount of the high boiling point refrigerant and the non-condensing gas containing a large amount of the low boiling point refrigerant are separated inside the shell Sa of the external condenser. The high-boiling-point refrigerant and the low-boiling-point refrigerant can be efficiently separated by utilizing the extra-tube condenser without using a gas-liquid separator, and the structure can be simplified accordingly.

According to the sixth aspect of the present invention, as shown in FIG. 8, in the header H2 on the condensed refrigerant take-out side of the in-pipe condenser, a condensate containing a large amount of high-boiling point refrigerant and a non-condensing gas containing a large amount of low-boiling point refrigerant. Can be separated, the high-boiling-point refrigerant and the low-boiling-point refrigerant can be efficiently separated by utilizing the in-pipe condenser without using a gas-liquid separator, and the structure can be simplified accordingly. it can.

According to the seventh aspect of the invention, as shown in FIG. 8 as well, the header H on the take-out side of the evaporated refrigerant of the in-pipe evaporator is shown.
In No. 1, it is possible to separate the non-evaporated liquid containing a large amount of high-boiling-point refrigerant and the evaporative gas containing a large amount of low-boiling-point refrigerant. The boiling point refrigerant can be efficiently separated, and the structure can be simplified accordingly.

According to the eighth aspect of the present invention, as shown in FIG. 9, in a relatively large-scale separate air heat source heat pump system for building air conditioning or the like, the outlet portion of the pressure reducing mechanism 3 of the main refrigerant circuit corresponds to a liquid head. If there is an increase in pressure, the temperature of the outlet side refrigerant of the pressure reducing mechanism 3 is high, but the pressure reducing means 30 provided separately from the pressure reducing mechanism 3 of the main refrigerant circuit does not cool the tank portion 6 with such a refrigerant. Since the low temperature refrigerant is cooled to cool the tank portion 6, the tank portion 6 can be sufficiently cooled, the liquefaction of the low boiling point component in the tank portion 6 can be promoted, and the amount thereof can be increased.

[0027]

FIG. 1 shows a heat pump type refrigerating apparatus according to a first embodiment, which includes a compressor 1, a four-way switching valve 10, a heat source side heat exchanger 2, a gas-liquid separator 51, a pressure reducing mechanism 3, and a use. The side heat exchangers 4 are sequentially connected by a refrigerant pipe. 11, 12, 1
Reference numerals 3 and 14 denote rectification check mechanisms that control the flow of the refrigerant in accordance with cooling and heating. In the refrigeration cycle system,
R22 as a high boiling point refrigerant and R13B1 as a low boiling point refrigerant
HFC as a mixed refrigerant or high boiling point refrigerant
134a is a mixed refrigerant using HFC32 as a low boiling point refrigerant, or HFC134 as a high boiling point refrigerant.
A mixed refrigerant or the like using HFC32 / 125 as a low boiling point refrigerant is enclosed.

During cooling, as indicated by the solid line arrow in FIG.
Chasing by the code, 1, 10, 2, 11, 51, 3, 12,
Refrigerant is caused to flow in the order of 4, 10, 1 and the heat source side heat exchanger 2 is used as a condenser and the use side heat exchanger 4 is used as an evaporator.

During heating, as indicated by the dotted arrow in FIG.
Chasing by code, 1, 10, 4, 13, 51, 3, 14,
Refrigerant is caused to flow in the order of 2, 10, 1 and the use side heat exchanger 4 is used as a condenser and the heat source side heat exchanger 2 is used as an evaporator.

In the above structure, the gas-liquid separator 51 constitutes the separation section 5 for separating the condensate containing a large amount of the high boiling point refrigerant and the non-condensing gas containing a large amount of the low boiling point refrigerant. or,
A tank portion 6 having a predetermined capacity is provided at the outlet of the decompression mechanism 3,
Inside the tank section 6, a heat exchange tube 60 is provided through which the low-temperature refrigerant b, which has been decompressed by the decompression mechanism 3, flows. And, the upper gas region of the gas-liquid separator 51 and the tank portion 6 which form the separation portion 5 are provided with a first opening / closing mechanism 71 including a solenoid valve or the like.
The tank portion 6 and the outlet-side low-pressure portion of the heat exchange pipe 60 are connected to each other via the communication passage 81 via a second communication passage 82 having a second opening / closing mechanism 72 also including an electromagnetic valve or the like.

Thus, both during cooling and during heating,
By opening the first opening / closing mechanism 71 and closing the second opening / closing mechanism 72, the low boiling point component is held inside the tank portion 6 and low capacity operation can be performed. On the other hand, while closing the first opening / closing mechanism 71, the second opening / closing mechanism 7
By opening 2, the low boiling point component stored in the tank 6 is released into the system of the refrigeration cycle, and high capacity operation can be performed. During low-capacity operation, the tank portion 6 is cooled by the lowest temperature refrigerant b before passing through the evaporator 4 or 2. Therefore, the liquefaction of the low boiling point component in the tank portion 6 can be promoted and stored. The amount of low boiling point components can be increased.

FIG. 3 shows a second embodiment, which is different from FIG. 1 in that the non-evaporated liquid containing a large amount of high boiling point refrigerant and the evaporative gas containing a large amount of low boiling point refrigerant are separated on the suction side of the compressor 1. Then, a low-pressure tank 90 having a predetermined capacity for storing the non-evaporated liquid containing a large amount of high-boiling-point refrigerant is provided, and the lower portion of the low-pressure tank 90 and the suction portion of the compressor 1 are provided with a third opening / closing mechanism 73 including an electromagnetic valve or the like. The point is that they are connected via a third communication passage 83 having a. In this case, the low boiling point refrigerant can be retained in the low pressure tank 90 by controlling the wetness of the outlet of the evaporator 4 or 2, and the control range can be further expanded.

FIG. 5 shows the third embodiment, and is different from FIG. 3 in that the low boiling point component and the high boiling point component are selectively stored in one tank portion 6. That is, the suction side of the compressor 1 is provided with a low-pressure separation section 9 having a relatively small capacity for separating the non-evaporated liquid containing a large amount of high-boiling-point refrigerant and the evaporative gas containing a large amount of low-boiling-point refrigerant. The lower portion of the portion 9 and the tank portion 6 are connected via a third communication passage 83 having a check mechanism 70 for allowing only the flow from the low pressure separation portion 9 to the tank portion 6 and a third opening / closing mechanism 73 composed of a solenoid valve. In addition, the upper gas region of the tank portion 6 and the low pressure portion in the refrigeration cycle are connected via a fourth pressure equalizing fourth communication passage 84 having a fourth opening / closing mechanism 74 including an electromagnetic valve or the like.

FIG. 6 shows a fourth embodiment, in which the heat exchanger 2 serving as a condenser is an outside condensation type having a shell Sa for releasing the refrigerant and a cooling water pipe Ta installed therein. I am trying. Inside the shell Sa of this extra condenser,
It is possible to separate a condensate containing a large amount of high-boiling-point refrigerant and a non-condensable gas containing a large amount of low-boiling-point refrigerant. Therefore, by utilizing this shell Sa, a condensate containing a large amount of high-boiling-point refrigerant and a low-boiling-point refrigerant. The separation unit 5 is configured to separate the non-condensable gas containing a large amount of. In addition, the heat exchanger 4 serving as an evaporator is provided with a shell Sb for generating cold water, a refrigerant pipe Tb installed therein, and headers H1 and H2 for taking in and out the refrigerant.
In-tube evaporation type is used. In the header H1 on the side of taking out the evaporated refrigerant in the in-pipe evaporator, it is possible to separate the non-evaporated liquid containing a large amount of the high boiling point refrigerant and the evaporated gas containing a large amount of the low boiling point refrigerant. Utilizing the header H1 on the refrigerant discharge side,
The low-pressure separation unit 9 is configured to separate the non-evaporated liquid containing a large amount of the high boiling point refrigerant and the evaporated gas containing a large amount of the low boiling point refrigerant.

FIG. 7 shows a fifth embodiment, which is applied to an air heat source heat pump chiller / heater. In this configuration, an air heat exchanger with a fan 20 is used as the heat source side heat exchanger 2, and a shell Sb for generating cold water or hot water is used for the use side heat exchanger 4, a refrigerant pipe Tb installed therein, and A water heat exchanger having headers H1 and H2 for taking in and out the refrigerant is used.

FIG. 8 shows a sixth embodiment, and is different from FIG. 7 in that the use side heat exchanger 4 is used to form a separation section 5 and a low pressure separation section 9. That is, the usage-side heat exchanger 4 includes a shell Sb that produces cold water or hot water, a refrigerant pipe Tb that is installed inside the shell Sb, and a header H for taking in and out the refrigerant.
1, H2, when the utilization side heat exchanger 4 is used as a condenser, the condensed refrigerant outlet side header H
In the inside of 2, it is possible to separate the condensate containing a large amount of high-boiling-point refrigerant and the non-condensable gas containing a large amount of low-boiling-point refrigerant. The separation unit 5 for separating the liquid and the non-condensable gas containing a large amount of the low boiling point refrigerant is configured.
When the utilization side heat exchanger 4 is used as an evaporator, the non-evaporated liquid containing a large amount of the high boiling point refrigerant and the evaporative gas containing a large amount of the low boiling point refrigerant are separated inside the header H1 on the extraction side of the evaporated refrigerant. Therefore, the low-pressure separation section 9 for separating the non-evaporated liquid containing a large amount of high-boiling point refrigerant and the evaporative gas containing a large amount of low-boiling point refrigerant is formed by utilizing the header H1 on the extraction side of the evaporating refrigerant. I have decided.

FIG. 9 shows a seventh embodiment, in which a heat source side heat exchanger 2 constituted by an air heat exchanger provided with a fan 20 is installed on the roof of a building, and the others are installed in a basement or the like, such as a building air conditioner. It is a relatively large separate air source heat pump system. Since this structure has a pressure increase corresponding to the liquid head at the outlet of the depressurizing mechanism 3 of the main refrigerant circuit, the tank unit 6 is decompressed by the low temperature refrigerant depressurized by the depressurizing means 30 provided separately from the depressurizing mechanism 3 of the main refrigerant circuit. It was made to cool.

[0038]

According to the invention described in claim 1, even if the capacity of the tank portion 6 or the amount of refrigerant filled in the refrigeration cycle system is not increased more than necessary, the low boiling point refrigerant in the tank portion 6 Liquefaction can be promoted, followability of capacity control can be improved, and the amount of refrigerant that can be retained in the tank portion 6 can be increased, so that the control range of capacity control can be expanded.

According to the second aspect of the invention, the tank portion 6
In addition to holding and releasing low-boiling components in the low-pressure tank 90, holding and releasing high-boiling components in the low-pressure tank 90 can be performed, a wide range of composition ratios can be changed, and the control range of capacity control can be further expanded. .

According to the third aspect of the present invention, the low boiling point refrigerant and the high boiling point refrigerant can be selectively retained in one tank portion 6, and a wide composition ratio can be achieved while minimizing the number of vessels having a large capacity. Can be changed, and the control range of capacity control can be further expanded.

According to the fourth aspect of the present invention, the high-boiling-point refrigerant and the low-boiling-point refrigerant can be satisfactorily separated by the gas-liquid separator 51 provided downstream of the heat exchanger serving as the condenser.

According to the fifth aspect of the invention, the high-boiling-point refrigerant and the low-boiling-point refrigerant can be efficiently separated by utilizing the shell Sa of the external condenser without using a gas-liquid separator. , The configuration can be simplified.

According to the sixth aspect of the present invention, the high boiling point refrigerant and the low boiling point refrigerant can be efficiently used by utilizing the header H2 on the take-out side of the condensed refrigerant of the in-tube condenser without using a gas-liquid separator. They can be separated, and the structure can be simplified accordingly.

According to the invention of claim 7, the high boiling point refrigerant and the low boiling point refrigerant are efficiently separated by utilizing the header H1 on the take-out side of the evaporated refrigerant of the in-pipe evaporator without using a special low pressure tank or the like. The configuration can be simplified accordingly.

According to the eighth aspect of the invention, the decompression means 30 provided separately from the decompression mechanism 3 of the main refrigerant circuit allows the decompression of the main refrigerant circuit in a relatively large-scale separate air heat source heat pump system such as a building air conditioner. Even when there is a pressure increase corresponding to the liquid head at the outlet of the mechanism 3, the tank 6
Can be sufficiently cooled, the liquefaction of the low boiling point component in the tank part 6 can be promoted, and the amount of the low boiling point component held can be increased.

[Brief description of drawings]

FIG. 1 is a piping diagram of a first embodiment of the present invention.

FIG. 2 is an explanatory view of the operation of the first embodiment.

FIG. 3 is a piping diagram of the second embodiment.

FIG. 4 is an explanatory view of the operation of the second embodiment.

FIG. 5 is a piping diagram of the third embodiment.

FIG. 6 is a piping diagram of the fourth embodiment.

FIG. 7 is a piping diagram of the fifth embodiment.

FIG. 8 is a piping diagram of the sixth embodiment.

FIG. 9 is a piping diagram of the seventh embodiment.

FIG. 10 is a piping diagram of a conventional example.

FIG. 11 is an explanatory diagram of conventional problems.

[Explanation of symbols]

5: Separation part, 51; Gas-liquid separator, 6; Tank part, 70;
Non-return mechanism, 71; first opening / closing mechanism, 72; second opening / closing mechanism,
73; third opening / closing mechanism, 74; fourth opening / closing mechanism, 81; first
Communication passage, 82; second communication passage, 83; third communication passage, 84;
Fourth communication passage, 9; low-pressure separation section, Sa, Sb; shell, T
a; cooling water pipe, Tb; refrigerant pipe, H1, H2; header, 3; pressure reducing mechanism, 30; pressure reducing means

Claims (8)

[Claims] 1. A refrigeration system using a non-azeotropic mixed refrigerant in which a mixed refrigerant of a high boiling point refrigerant and a low boiling point refrigerant is enclosed in a refrigeration cycle system in which compression, condensation, decompression and evaporation are repeated, Separation part (5) for separating a condensed liquid containing a large amount of high boiling point refrigerant and non-condensed gas containing a large amount of low boiling point refrigerant, and a tank part (6) for exchanging heat with the low temperature refrigerant after depressurizing the condensed liquid containing a large amount of high boiling point refrigerant And the upper gas region of the separation part (5) and the tank part (6) are connected via the first communication passage (81) having the first opening / closing mechanism (71), and the tank part (6) is provided. A refrigeration system using a non-azeotropic mixed refrigerant, characterized in that the low pressure part in the refrigeration cycle is connected to the low pressure part via a second communication passage (82) having a second opening / closing mechanism (72). 2. A low-pressure tank (9) of a predetermined capacity for separating the non-evaporated liquid containing a large amount of high-boiling-point refrigerant and the evaporative gas containing a large amount of low-boiling-point refrigerant to store the non-evaporated liquid containing a large amount of high-boiling-point refrigerant.
0), and the lower part of the low-pressure tank (90) and the suction part of the compressor are connected via a third communication passage (83) having a third opening / closing mechanism (73). Refrigeration system using boiling mixed refrigerant. 3. A low-pressure separation section (9) for separating a non-evaporated liquid containing a large amount of high-boiling-point refrigerant and an evaporative gas containing a large amount of low-boiling-point refrigerant, the lower part of this low-pressure separation section (9) and a tank section (6). ) Through a third communication passage (83) having a non-return mechanism (70) that allows only the flow from the low pressure separation section (9) to the tank section (6) and a third opening / closing mechanism (73). The connection is made, and the upper gas region of the tank part (6) and the low pressure part in the refrigeration cycle are connected through a fourth pressure equalizing fourth communication passage (84) having a fourth opening / closing mechanism (74). Refrigeration system using the non-azeotropic mixed refrigerant. 4. A separation unit (5) for separating a condensate containing a large amount of high-boiling-point refrigerant and an uncondensed gas containing a large amount of low-boiling-point refrigerant.
Is a gas-liquid separator (51) interposed downstream of the heat exchanger serving as a condenser.
A refrigeration system using the described non-azeotropic mixed refrigerant. 5. A heat exchanger serving as a condenser comprises a shell (Sa) for releasing a refrigerant, and a cooling water pipe (T) installed therein.
(a) is an extra-condensation type, and the separation part (5) for separating a condensate containing a large amount of high-boiling-point refrigerant and a non-condensable gas containing a large amount of low-boiling-point refrigerant is a shell of the extra-tube condenser. (S
A refrigeration system using the non-azeotropic mixed refrigerant according to claim 1, 2 or 3, which is a). 6. A heat exchanger serving as a condenser, wherein a shell (Sb) for generating hot water, a refrigerant pipe (Tb) installed therein,
And a pipe condensing type having headers (H1, H2) for taking in and out the refrigerant, for separating a condensate containing a large amount of high boiling point refrigerant and a non-condensing gas containing a large amount of low boiling point refrigerant (5). Is a header (H2) on the take-out side of the condensed refrigerant, The refrigeration system using the non-azeotropic mixed refrigerant according to claim 1, 2 or 3. 7. A heat exchanger serving as an evaporator, wherein a shell (Sb) for generating cold water, a refrigerant pipe (Tb) installed therein,
And a pipe evaporation type having headers (H1, H2) for putting in and out the refrigerant, and a low-pressure separation section (9) for separating a non-evaporated liquid containing a large amount of a high boiling point refrigerant and an evaporated gas containing a large amount of a low boiling point refrigerant. ) Is a header (H1) on the take-out side of the evaporated refrigerant, and the refrigerating apparatus using the non-azeotropic mixed refrigerant according to claim 3. 8. The tank section (6) exchanges heat with a low-temperature refrigerant whose pressure is reduced by a pressure reducing means (30) provided separately from the pressure reducing mechanism (3) of the main refrigerant circuit. A refrigeration system using the non-azeotropic mixed refrigerant as described above.